I fill the bags with ornaments that we already had (special ones that mean something to us), and chocolates.
See the 'How to' after the jump. And here is a super cute round-up of Advent Calendars.
You can skip these first few steps by buying already made craft bags, but I went the full DIY approach and made my own bags out of Christmas wrapping paper.
I cut rectangles from wrapping paper 8in W x 7.5in H (20cm W x 19cm H)
Fold one side inward and leave about an inch salvage at the end. Fold the salvage over and tape.
To complete the bottom, fold a triangle about an inch from the bottom on the right and left side and tape. Fold the bottom over and tape.
Put little trinkets in each bag. Fold the top over and staple closed.
You can make your own number tags or use these ones, December 1-8 here, December 9-16 here, December 17-24 here, and lonely December 25 here. Print the tags on regular copy paper and fold over the top inch to go over the top of the bag. Put a little piece of double sided tape on the fold and on the bottom of the tag.
I pinned the bags of trinkets on to a cork-board with linen over it, and voila!
Let the fun begin!